We're dividing 20638 by 42 
Let's see how many times 42 fits into 20638.

Advancing to step 1:
42 can be fit into 2 0 times, resulting in a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Include the next digit (0) from the dividend after 2, then repeat: 20 / 42

Going ahead to step 2:
20 divided by 42 is 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 20, we end up with 20.
Include the next digit (6) from the dividend after 20, then repeat: 206 / 42

Advancing to step 3:
When dividing 206 by 42, we get 4 with a remainder of 38.
The next digit of our result is 4. 
Result so far: 4.0
Deduct 168 from 206 and we're left with 38.
Fetch the next digit (3) from the dividend, attach it to 38 and continue: 383 / 42

Let's proceed to step 4:
The number 42 fits into 383 9 times, leaving a remainder of 5.
Use 9 as the next digit of our solution. 
Result so far: 49.0
Deduct 378 from 383 and we're left with 5.
Append the next digit (8) from the dividend to 5 and continue with: 58 / 42

Advancing to step 5:
When dividing 58 by 42, we get 1 with a remainder of 16.
Put 1 as the next digit of the answer. 
Result so far: 491.0
If we subtract 42 from 58, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 6:
42 goes into 160 3 times with a remainder of 34.
The next digit of our result is 3. 
Result so far: 491.3
Deduct 126 from 160 and we're left with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Moving on to step 7:
When dividing 340 by 42, we get 8 with a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 491.38
Subtract 336 from 340 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Let's proceed to step 8:
42 can be fit into 40 0 times, resulting in a remainder of 40.
Put 0 as the next digit of the answer. 
Result so far: 491.38
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Advancing to step 9:
400 divided by 42 is 9 with a remainder of 22.
Put 9 as the next digit of the answer. 
Result so far: 491.3809
Deduct 378 from 400 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 10:
If we divide 220 by 42, we get 5 and a remainder of 10.
Record the quotient 5 as the next digit in the result. 
Result so far: 491.38095
Subtracting 210 from 220 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 11:
42 goes into 100 2 times with a remainder of 16.
The number 2 becomes the next digit in our result. 
Result so far: 491.380952
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 12:
160 divided by 42 is 3 with a remainder of 34.
Write down 3 as next digit of the result. 
Result so far: 491.3809523
Deduct 126 from 160 and we're left with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Advancing to step 13:
The number 42 fits into 340 8 times, leaving a remainder of 4.
Record the quotient 8 as the next digit in the result. 
Result so far: 491.38095238
If we subtract 336 from 340, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

In conclusion, the division gives 491.38095238 with a balance of 4e-09.